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Cat3750X-eBGP failover from Master to Member


I would like to know about the eBGP specification on Cat3750X stackwise+ failover from Master to Member.


3750X-1-StackMaster    - Gi1/0/1 ---- F0/1 - 3560
3750X-2-StackMember  - Gi2/0/1 ---- F0/2 - 

SVI10( ---- SVI10(
 BGP AS1 -------- eBGP -------- BGP AS2

*Multi-Chassis EtherChannel - Mode ON (Po1)


When 3750X-1-StackMaster power down occurs then 3750X-2-StackMember takes over the routing table and also eBGP session right? I mean that it does not occur BGP peer down and up (Flapping) .


I appreciate if you let me know any related information.


Best Regards,


Masanobu Hiyoshi


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When a 3750 stack's master fails, there can be a brief interruption to L3 services.  To avoid a routing flap, the 3750 supports NSF for some routing protocols (don't recall if this includes BGP).

Also, don't know if it applies to BGP, but for some master switch overs, it helps if you've configured persistent MAC.  [edit - BTW, I believe port-channels are impacted by a change in master MAC.]

New Member

 Hello JosephThank you very


Hello Joseph

Thank you very much for your info. According to your keyword "NSF"

I have been investigating through Cat3750X, it may be configurable like below.

router bgp 1
 bgp graceful-restart restart-time x
 bgp graceful-restart stalepath-time x
 bgp graceful-restart

However I have to understand the timer value and impact if it modifies.


And another information is that I think BGP NSF also must re-establish the session.

You can see the information on the following URL.

[BGP Nonstop Forwarding (NSF) Awareness ]

*Quote from the URL.

After an RP switchover occurs, the NSF-capable router reestablishes the session with the BGP peer. 
In establishing the new session, it sends a new graceful restart message that identifies the NSF-capable router as having restarted. 


Best Regards,


Masanobu Hiyoshi

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